Syringe

ABSTRACT

A syringe for the injection of radioactive medicinal and diagnostic compositions into the body, the syringe having a cylindrical body of lead glass with a hypodermic needle attached at one end thereof and at the other end, a plunger of stainless steel for slidable engagement with the inner surfaces of the wall of such cylindrical body, the plunger being coated at least along its surfaces adjacent the wall of the cylindrical body with a coating material which is a resilient polymeric material, rubber or combinations thereof.

United States Patent [56] References Cited UNITED STATES PATENTS 1,753,287 4/1930 Failla 128/111 X 3,150,801 9/1964 Hamilton 128/218 X Primary Examiner-Samuel Koren Attorney-M. N. Cheairs ABSTRACT: A syringe for the injection of radioactive medicinal and diagnostic compositions into the body, the syringe having a cylindrical body oflead glass with a hypodermic needle attached at one end thereof and at the other end, a plunger of stainless steel for slidable engagement with the inner surfaces of the wall of such cylindrical body, the plunger being coated at least along its surfaces adjacent the wall of the cylindrical body with a coating material which is a resilient polymeric material, rubber or combinations thereof.

PATENTEU DEE?! am FIGURE 2 I. w; JTOR.

OTHEL L. PIRTLE JR ATTORNEY SYRINGE BACKGROUND OF THE INVENTION The present invention relates to a syringe. More particularly, the present invention relates to a syringe for use in the injection of medicinal or diagnostic radioactive materials into the body.

Within recent years, there has been a wide and continuously increasing acceptance of the use of radioisotopes for the treatment of various body malfunctionsand for the diagnosis of such malfunctions. Such use involves the injection of the radioisotope into the body of the patient. generally by means of a syringe. As a result of the radioactivity of the radioisotope, however, considerable hazard is involved with respect to those responsible for injecting such radioisotope within the patients body. This hazard is sufficiently serious that it is common practice to very frequently rotate the technical personnel responsible for injection of the radioisotopes in order to prevent excess exposure to radioactivity of any particular technician. Such rotation results in several people being required in order to insure the availability at all times of a technician who has not been overexposed to radiation, for injection of radioisotopes.

It has been proposed to shield the syringe with materials substantially impervious to the passage of radioactivity, particularly the gamma rays most often encountered in medical and diagnostic radiology, to thereby prevent exposure of the technician to the radiation of the radioisotope being injected. However, the use of such shields isvery cumbersome and prevents the technician making the injection from being able to determine if injection has been properly made in the vein of the person being injected. Further, the technician is unable to see the body of the syringe and thereby determine the amount of material injected. Additionally, such shields generally fail to protect against the passage of radioactivity upward along the axis of the syringe and through the plunger which is being depressed by the technician.

It is now an object of the present invention to provide a new and improved syringe for the injection and handling of radioactive components.

Another object of the present invention is to provide a new and improved syringe for the injection and handling of radioactive components which minimizes exposure of those handling such syringe to radiation.

Still another object of the present invention is to provide a new and improved syringe for the injection and handling of radioactive components which can be repeatedly utilized by the same person without harmful exposure to radiation from the radioactive components within such syringe.

Additional objects will become apparent from the following description of the invention herein disclosed.

SUMMARY OF THE INVENTION The present invention, which fulfills these and other objects, is a syringe comprising a cylindrical body having connected at one end thereof, a hypodermic needle, saidcylindrical body being of lead glass having a density within the range of 2 to 6.5, and a plunger for slidable engagement with the inner wall of said cylindrical body, said plunger being of stainless steel and having at least the portion. of said plunger adapted for slidable engagement with the inner wall of said cylindrical body coated with a soft resilient material selected from the group consisting of resilient polymeric materials, rubber and combinations of these.

By use of the syringe of the present invention, the danger of DESCRIPTION OF THE DRAWINGS FIG. 1 of the drawing is a longitudinal cross-sectional view of the syringe of the present invention.

FIG. 2 of the drawing illustrates in cross section, an embodiment of a detail of the syringe of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE PRESENT INVENTION For description of the preferred embodiments of the present invention, reference is made to the accompanying drawing. Referring to the drawing, the syringe of the present invention includes a cylindrical body 10. To tip 11 of the lower end 12 of cylindrical body 10, is attached a hypodermic needle l3. Afiixed to the opposite end of cylindrical body 10 and extending outward therefrom on opposite sides, are finger grips 14 which are employed to aid in depressing plunger 15 within cylindrical body 10.

Cylindrical body 10 is of lead glass having a density of approximately 2 to about 6.5, preferably 3.0 to 6.2. This lead glass will substantially alleviate the passage of gamma and X- rays emitted by most commonly employed medicinal and diagnostic radioisotopes. The optimum density of the lead glass will depend upon the particular radioisotope and the radioactivity omitted thereby. Additionally, the lead glass of the cylindrical body 10 must be of a thickness which will permit observation of the material within body 10. Generally, with the lead glass densities hereinabove described, this thickness will be within the range of 2 to 5 millimeters, preferably 2.5 to 4 millimeters. A particularly useful cylindrical body for use in the syringe of the present invention is one having a wall thickness of approximately 3 millimeters and consisting of lead glass having a density of about 3.2. Generally, cylindrical body 10 will be provided with graduated markings to facilitate observation of the quantity of the radioisotope containing solution within said cylindrical body.

In the drawing, hypodermic needle 13 is illustrated as connected to the lower end 12 of cylindrical body 10 by means of threads 16 which connect to tip 11. However, hypodermic needle 13 may be attached to cylindrical body 10 by any other means available, such as by locking in place or by frictional contact of the attaching portion of the needle to the tip 11.

If desired, lower end 12 of cylindrical body 10 may be of a metal such as stainless steel, which is substantially impervious to the passage of gamma and X-rays instead of the lead glass of which the walls of cylindrical body l0are constructed.

Fitting within cylindrical body 10 and in slidable engagement with the internal surface thereof, is plunger 15. Fixed to the upper end of plunger 15, is a plunger head 17 which is used by the operator for depression of plunger 15. On the lower end of plunger 15, a plunger tip 18 is shown. This plunger tip l8consists of a soft resilient material selected from thegroup consisting of resilient polymeric materials, rubber and combinations thereof. Among the polymeric materials useful as the plunger tip are such materials as the fluororcarbon resins, particularly tetrafluroethylene, generally referred to as Teflon (registered trademark of Du Pont for its fluororcarbon resins). Additionally, polyethylene and polypropylene, particularly those of relatively low density, are useful as the resilient polymeric material which may be used to form the plunger tip 18.

The configuration of plunger tip 18 may vary considerably. It may constitute no more than a relatively thin layer of the soft resilient material on the end of plunger 15. More often, however, plunger tip 18 will be in the form of a sealing plug of the soft resilient material having a thickness of several millimeters. In this fashion, the plunger tip 18 may be a cylindrical plug fixed to the lower end of plunger 15 and extending into contact throughout its cylindrical surface with the inner wall of cylindrical body 10. In another embodiment, plunger tip 18 may be in the form of a cylindrical plug having a diameter less than the inner diameter of the cylindrical body but having one or more sealing rings 19 of the same or another soft resilient material extending annually therearound, as illustrated in FIG. 2, for sealing contact with the inner wall of cylindrical body 10. Many additional modifications of the plunger tip 18 may be made, however, such modifications in so long as they involve the use of a plunger tip consisting of soft resilient materials, as hereinabove defined, are within the spirit j and scope of the present invention.

While it is preferred to provide a plunger tip 18 on the lower end of the plunger 15, it is within the scope of the present invention that plunger 15 not be so provided with plunger tip 18. In such instances, the metal plunger will itself be in contact at its lower end with the radioactive materials within cylindrical body 10.

The external surface of plunger 15 is provided with coating 20 of soft resilient material to act as a sealing and protective coating and to aid in maintaining plunger 15 in slidable engagement with the inner wall of cylindrical body 10. Coating 20 may be continuous over the entire outer surface of plunger 15 to the extent that plunger 15 will be in contact with the inner walls of cylindrical body or coating 20 may comprise a series of annular rings of soft resilient material spaced apart along the length of that portion of plunger which will contact the inner surface of cylindrical body 10. The soft resilient material employed as coating generally is one selected from the group hereinabove defined for uses plunger tip l8.

Particularly preferred for the coating are the fluororcarbon resins, particularly tetrafluroethylene (Teflon).

What is claimed is:

l. A syringe comprising a cylindrical body having connected at one end thereof a hypodermic needle, such cylindrical body having a wall of lead glass having a density within the range of 2 to 6.5, said wall of said cylindrical body having a thickness of 2 to 5 millimeters, and a plunger for slidable engagement with the inner wall of said cylindrical body, said plunger being of stainless steel and having at least the portion of said plunger adapted for slidable engagement with the inner wall of said cylindrical body coated with a soft resilient material selected from the group consisting of resilient polymeric materials, rubber and combinations of these 2. The syringe of claim 1 wherein the inner end of said plunger is provided with a plunger tip comprising a soft resilient material selected from the group consisting of resilient polymeric materials, rubber and combinations of these.

3. The syringe of claim 1 wherein the density of said lead glass is within the range of 3.0 to 6.2.

4. The syringe of claim 1 wherein said thickness is within the range of 25 to 4 millimeters. 

1. A syringe comprising a cylindrical body having connected at one end thereof a hypodermic needle, such cylindrical body having a wall of lead glass having a density within the range of 2 to 6.5, said wall of said cylindrical body having a thickness of 2 to 5 millimeters, and a plunger for slidable engagement with the inner wall of said cylindrical body, said plunger being of stainless steel and having at least the portion of said plunger adapted for slidable engagement with the inner wall of said cylindrical body coated with a soft resilient material selected from the group consisting of resilient polymeric materials, rubber and combinations of these
 2. The syringe of claim 1 wherein the inner end of said plunger is provided with a plunger tip comprising a soft resilient material selected from the group consisting of resilient polymeric materials, rubber and combinations of these.
 3. The syringe of claim 1 wherein the density of said lead glass is within the range of 3.0 to 6.2.
 4. The syringe of claim 1 wherein said thickness is within the range of 2.5 to 4 millimeters. 